Re: [PATCH v8 25/25] gpu: nova-core: mm: Add PRAMIN aperture self-tests

[Joel Fernandes <joelagnelf@nvidia.com>]

On Thu, Mar 05, 2026 at 04:26:52PM +0900, Alexandre Courbot wrote:
> On Tue Mar 3, 2026 at 5:11 AM JST, Joel Fernandes wrote:
>> The PRAMIN aperture window register changed on Hopper+: pre-Hopper uses
>> NV_PBUS_BAR0_WINDOW while Hopper+ uses NV_XAL_EP_BAR0_WINDOW. Our
>> current code only programs the former, so we'd need a HAL to support
>> both. For now, V2-only is the safe choice. I've updated the comment to
>> explain this.
>
> I see, but then it seems that the correct check would be against the
> `Chipset`, not the version of the page table format? I understand the
> two are linked transitively, but they are in practice different engines.

Alex, makes sense, so I'll change it to the following then (still testing
but here is a preview):

@@ -439,17 +458,21 @@ pub(crate) fn run_self_test(
     dev: &kernel::device::Device,
     bar: Arc<Devres<Bar0>>,
     vram_region: Range<u64>,
-    mmu_version: super::pagetable::MmuVersion,
+    chipset: crate::gpu::Chipset,
 ) -> Result {
-    use super::pagetable::MmuVersion;
+    use crate::gpu::Architecture;
 
     // PRAMIN uses NV_PBUS_BAR0_WINDOW which is only available on pre-Hopper GPUs.
-    // Hopper+ uses a different register (NV_XAL_EP_BAR0_WINDOW), requiring a HAL.
-    if mmu_version != MmuVersion::V2 {
+    // Hopper+ uses NV_XAL_EP_BAR0_WINDOW instead, requiring a separate HAL that
+    // has not been implemented yet.
+    if !matches!(
+        chipset.arch(),
+        Architecture::Turing | Architecture::Ampere | Architecture::Ada
+    ) {
         dev_info!(
             dev,
-            "PRAMIN: Skipping self-tests for MMU {:?} (only V2 supported)\n",
-            mmu_version
+            "PRAMIN: Skipping self-tests for {:?} (only pre-Hopper supported)\n",
+            chipset
         );
         return Ok(());
     }

-- 
Joel Fernandes